While watching the construction of steel girders to support power lines in 1911, A. C. Gilbert conceived the Erector Set, an educational toy that encouraged kids to create their own miniature buildings. Unlike its British cousin, the Meccano toy, Gilbert’s simple design fashioned sturdy one-inch square girders with just two bolts. Businessmen and industrial psychologists hailed the toy that put play to work and encouraged children’s “constructive instincts.” A national advertising campaign, the first ever for a toy, in the Saturday Evening Post and Popular Mechanics launched the Erector Set in 1913. In those days, American society did not encourage girls to pursue technical careers. “Hello, Boys!” the ads exhorted heartily, “Make Lots of Toys!” Appearing around the same time as Lincoln Logs and Tinkertoys, Erector Sets introduced boys to engineering and the structural principles of modern skyscrapers. Redesigned in 1924, the new basic set encouraged more complex construction. Specialized kits with electric motors included allowed kids to create trains, steam shovels, Ferris wheels, and Zeppelins. Faced with wartime metal shortages in the 1940s, the company introduced wooden sets. In the 1960s, the Gabriel Co. bought the popular toy, but sales slowed in the 1970s. In 1980, the manufacturer discontinued the line.